Problem: Simplify the following expression: $k = \dfrac{-2n}{4} + \dfrac{-2n}{4}$
Explanation: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{-2n - 2n}{4}$ Combine like terms: $k = \dfrac{-4n}{4}$ Simplify by dividing numerator and denominator by 4: $k = \dfrac{-n}{1}$ $k = -n$